Combined steam and air engine



E. M.'STBANGE. Combined Steam and Air Engine.

No. 237,708. Patented-Feb. 15,1881.

- FIEIT' N.FEIERS, PHOTO-LI'IHOGRAFHER. WASHINGTON 0 C.

UNTTED STATES EDWARD M. STRANGE, OF BALTIMORE, MARYLAND.

COMBINED STEAM AND AIR ENGINE.

SPECIFICATION forming part of Letters Patent No. 237,708, dated February 15, 1881. Application filed January 20, 1880. (ModeL) To all whom it may concern:

Be it known that I, EDWARD M. STRANGE, of the city of Baltimore and State of Maryland, have invented a Combined Steam and Air Engine, of which the following is a specification and I do hereby declare that in the same is contained a full, clear, and exact description of my said invention, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The said invention consists in combining, with a steam-generator, an engine in which one side only of its piston is acted on by the steam, the other side of the said piston being used to compress air which is forced into the steamgenerator, and after passing through the water therein is combined with the steam and used in connection therewith as a prime mover for the engine.

In the further description of my said invention which follows reference is made to the accompany drawings, forming a part hereof, and in which- Figure lvis a vertical section of the steamgenerator, together with parts of the improved engine. Fig. 2 is a cross-section of the generator on the dotted line a." y.

Similar letters of reference indicate similar parts in both the views.

In the said drawings, A is the steam-generator, consisting of the steam and water chamber a and fire-box b. The fire-box is separated from the steam and water chamber by a plate, 0, secured in place in any appropriate manner. Tubes (1, closed at their upper end, extend into the water-chamber to increase the heating-surface of the generator.

Fuel, preferably coal, although hydrocarbon fluid or other combustible material may be used, is introduced to the fire-box through the pipe B, which is fitted with cocks e e to allow of the introduction of the charge without bringing the contents of the fire-box in communication with the outer air during the feeding operation. Fuel may also be supplied through the door, in which case the compressed air and gases in the fire-box at the time are lost. The fuel may however be fed to the fire-box through the central pipe, 0, which is fitted with cocks f f, arranged in a manner similar to the ones ein the pipe B.

The central pipe, 0, is also used as a smokepipe to carry off the products of combustion of fuel in the fire-box when the firein the same is first started.

D is an air-pipe, connecting the fire-box at at a point below the grate-bars g with the end of the engine-cylinder E, which is used'as an air-compressor, having a branch, 9, leading to the interior of the water-chamber of the gen-' erator.

The fire-box is first charged with fuel, which is ignited in the usual manner, after which the cocksf in the central pipe, G,are opened to allow of the escape of smoke from the fire-box. When steam of sufficient tension is generated to operate the engine it is put in operation and air forced to below the gratebars in the fire-box. The cocks in the pipe 0 are then closed, \vhen'the products of COIllbfiS'DlOllZtlB conducted from the central pipe, 0, to the water in the generator by means of the pipes h, which are provided with check-valves h to prevent the passage of water to the fire-box when the said box is relieved from internal air pressure, established as aforesaid. The compressed air may, however, be delivered directly to the water or to the steam-space of the generator through the branch air-pipe g. Steam and air, or the same and the products of combustion to operate the engine, are conducted thereto by way of the pipe *5. The gases and products of combustion, in ascending to the surface of the water after escaping from the pipes h, are scattered by means of a sieve or grating, F, and foaming or priming of the water in the generator is, to a great extent, prevented by securin g a disk, Gr, around the central pipe, (J, at a suitable distance above the water-line '0 w. A sieve or perforated plate, H, is also secured a short distance below the steam-pipe t, to further reduce foaming or priming of the water.

In charging the fire-box when the same is under pressure, either the central pipe, 0, or the side pipe, B, may be used. The cocks in these pipes are preferably placed at such distance apart as to enable the intervening section of pipe to hold a full charge of fuel, which is deposited in the firebox by opening the lower cook, the upper one being closed.

In order to allow the compressed air to be delivered directly to the water or steam in the generator, the pipes D and g are provided with stop-cocks, and the latter pipe with a check-valve, g.

The fire-box has an air-tight door, K, hava glass-covered aperture to enable the attendant to see the condition of the fuel during its combustion. An air-tight door, L, situated below the grate-bars, is opened in removing the ashes. As before stated, the engine-piston is actuated by the combined steam and air in one direction only, the return of the piston being effected, as in all sin gle-actin g non-condensin g engines, by the momentum of the fly-wheel. Supposing the cylinder E to be filled with air at the atmospheric pressure admitted to the cylinder through the check-valve 7c, and the piston commencing its compressing-stroke, the resistance at first met with by the piston is comparatively slight; but as the piston advances the air-pressure is increased until an equilibrium of pressure upon the two sides of the piston is obtained. The combined steam and air now ceases to act as a motor, and the remainder of the compressing-stroke and the entire return stroke of the piston are, conse' qnently, effected by the momentum of the flywheel, which brings the piston to its startingpoint to be again propelled by the combined steam and air under boiler-pressure, as before described.

The heat evolved in the compression of air is utilized in superheating the steam, the heat being conveyed to the steam by means of the Wall of the cylinder, thus preventing the usual loss from condensation of steam in the cylinder, while at the same time the temperature of the air is sufficiently reduced to preventinjury to the packing of the various stuiiingboxes.

I make no claim to the construction of the generator, as the same contains few, if any, new features; but

What I claim is- In combination with a steam-generator, an cngine-cylinder one end of which is adapted as an air-compressor to force air to the said generator, and with this View connected to the said generator by means of a suitable air-pipe having a valve therein opening toward the said generator, the other end of the said cylinder being connected to the steam-space of the generator through the medium of appropriate pipes and valveopenings, substantially as and for the purpose herein specified.

EDNARD M. STRANGE. Witnesses:

HARRY V. ALBAUGH, WM. T. HOWARD. 

